Nearly 1 in 10 pregnant women in the U.S. report past-month alcohol use. Strong evidence connects prenatal alcohol exposure with a spectrum of conditions known as Fetal Alcohol Spectrum Disorders (FASDs), with consequences including reductions in brain volume, neurochemical and connectivity-related abnormalities, executive functioning deficits, and preterm birth. The burden of these consequences is disproportionately borne by African-Americans. Screening, Brief Intervention, and Referral for Treatment (SBIRT) has been recommended as a key intervention for pregnant women by the American College of Obstetricians & Gynecologists and the National Task Force on Fetal Alcohol Syndrome/Fetal Alcohol Effect. SBIRT has clear advantages, including (a) its proactive and universal approach; and (b) its use of a single motivational session that is brief enough to be acceptable to a high proportion of patients, even among those with little interest in treatment. Unfortunately, provider time, training, and fidelity are tremendous obstacles for SBIRT implementation, and implementation challenges are associated with reductions in effectiveness. Technology- delivered SBIRT (e-SBIRT) may address these obstacles. e-SBIRT requires far less time and training on the part of providers, facilitates disclosure, and can be disseminated with perfect fidelity. In the first randomized trial of e-SBIRT with pregnant women, we developed a single-session e-SBIRT that received high satisfaction ratings and yielded odds ratios in the medium range for alcohol abstinence and a positive birth outcome. A subsequent trial with women in a reproductive health setting showed this approach to be equivalent to person- delivered SBIRT and superior to enhanced usual care, at far less cost. This exciting potential, however, must be optimized and validated carefully prior to implementation. The proposed study will build upon the pilot trial by testing whether the intervention reduces alcohol use among pregnant women screening positive for alcohol risk. We will also use intervention optimization techniques (Multiphase Optimization Strategy, or MOST) to evaluate the extent to which intervention effects can be enhanced by adding subsequent booster sessions via participants? own mobile devices, and/or tailored text messaging. Specifically, we will (a) finalize booster session and text message content with iterative participant feedback, and (b) randomly assign pregnant women screening positive for alcohol risk (N = 384) to a 3 (no brief intervention; one session; or one session plus two boosters) X 2 (SMS present or not present) factorial trial. The primary analysis will test for dose- response effects of the e-intervention on alcohol use during pregnancy. Secondary analyses will examine main and interaction effects of tailored text messaging, as well as intervention effects on birth outcomes. Exploratory analyses will examine theory-driven mediators and moderators of intervention efficacy, as well as intervention effects on additional drinking-related outcomes (e.g., days of binge use). If successful, the proposed study would yield an optimized, practical, and readily disseminated method for prevention of FASD.